Quantification of convection velocity and dominant scale of large-scale structures by high-speed schlieren imaging

Toshinori Kouchi, Goro Masuya

Research output: Chapter in Book/Report/Conference proceedingConference contribution

2 Citations (Scopus)

Abstract

We proposed a new method to evaluate simultaneously both convective velocity and scale of dominant turbulent structures captured in a high speed framing schlieren movie. We took 90 time-series schlieren images of a transverse jet into a Mach 2 supersonic flow with 1 MHz sampling. We focused on periodical image gradations due to the turbulent structures within the jet and boundary layer. We remapped the image intensities on the structures along their trajectory as a time-space map. The time-space map showed swept stripe patterns. The presence of the stripe patterns indicates stable structures were periodically generated and convected downstream. Slope of the stripes corresponds to the convective velocities of the structures. Cycles in the space- and time-directions of the stripes correspond to the scale and formation cycle of the dominant structure. Two-dimensional Fourier transform efficiently extracted the dominant ones from the time-space map. We demonstrated this newlyproposed method using two-dimensional Fourier transform accurately evaluated the convective velocity and scale of the dominant turbulent structures within the jet and boundary layer.

Original languageEnglish
Title of host publication48th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit 2012
Publication statusPublished - Dec 1 2012
Externally publishedYes
Event48th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit 2012 - Atlanta, GA, United States
Duration: Jul 30 2012Aug 1 2012

Publication series

Name48th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit 2012

Other

Other48th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit 2012
CountryUnited States
CityAtlanta, GA
Period7/30/128/1/12

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ASJC Scopus subject areas

  • Energy Engineering and Power Technology
  • Aerospace Engineering
  • Control and Systems Engineering
  • Electrical and Electronic Engineering
  • Mechanical Engineering

Cite this

Kouchi, T., & Masuya, G. (2012). Quantification of convection velocity and dominant scale of large-scale structures by high-speed schlieren imaging. In 48th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit 2012 (48th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit 2012).